Spring-jack wedge.



No. 810,596. I PATENTED JAN. 23, 1906. G. A. ZUNDELV SPRING JACK WEAPPLIGATION FILED NOV. o4.

. form of my 1m rovements.

UNITED STATES PATENT OFFICE.

GUSTAVE A. ZUNDEL, OFNEW YORK, N. Y., .ASSIGNOR TO J. H. BUNNELL ANDCOMPANY, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Patented Jan. 23, 1906.

Application and November 17. 1904. Serial No. 233,070.

To alt whom it may concern.- Be it known that I, GUSTAVE A. ZUNDEL, acitizen of the United States, and a resident of New York city, countyand State of New York, have invented Im rovements in Spring- JacklNedges, of whic the following is a specification.

This invention relates to spring-j ack wedges or like electrical contactplugs used for switchboards, &c., and has for its object to so con--struct such a wedge that the usual strain on the flexibleconducting-wires in the manipulation of the wedge will not betransmitted to the points of soldering to or other electrical connectionwith the metallic contact-strips of the wedge.

In the accompanying drawings, Figure 1 is a plan view of a spring-j ackwedge of a usual form, to which my improvements may be applied drawn ona large scale for clear show- 1ng.- Fig. 2 is a side or edge view of thewedge shown in Fig. 1, which view illustrates one Fig. 3 is a centralsectional p an of the insulating piece or handle of the wedge shown inFigs. 1 and 2, and Fig. 4 is a sectional view taken on line 4 4 of Fig.3.

In the construction shown in the drawings the two fiat metalcontact-strips A A, Figs. 1 and 2, are suitably secured to and insu atedfrom each other by the insulating piece or handle B, which here formsthe body portion of the wedge. The strips A A have ent-over portions a alying .in the recesses in the sides of the insulating piece or bod B,and the ends of the conducting-wires O pass through perforations b 1),Figs. 3 and 4, 1n the handle end of the insulating piece or body B andare soldered or otherwise electrically connected to the bent-overortions a a of the contact-strips A A, as at Fig. 2. This portion of thewedge where the soldering is made is usuall covered, as by winding cordD around the evice,'and a rubber tubing, such as shown at E, in dottedlines in Figs. 1 and 2, may be laced over the handle and parts of thecon ucting-wires adjacent thereto.

The wedge so far described is a usual form; but there is a defect inthis construction, inasmuch as the constant pull on the wires C C inremoving the wedge from the spring-jacks tends to break the connectionbetween the wires and the contact-strips A a- A a. By my presentinvention I provide for firmly holding the wires in the wedge at a pointor points beyond the soldering, whereby strain on the wires outside thewedge cannot be transmitted to the points of electrical connection.Various ways may be employed for accomplishing my object; but thepreferred form is shown in the drawings and consists in providingerforations, such as 12 12 in the body or insu ating piece B in atransverse direction to the perforations, b b,Figs. 2, 3, and 4, wherebythe conducting-wires C C may be sewed to the piece B. The erforations bb are preferably made throng the body B at opposite walls of theperforations b 1), Figs. 3 and 4, that the sewing-threads F, Fig. 2, maypass through the covering of the wires O O. Also depressions or groovesb b are preferably made in the body B at the ends of the erforations bIf, whereby the threads may e fastened and covered or cemented-withinthe contour of the handle.

I do not limit my invention to the particular form of contact wedge orplug shown nor to the particular manner of securmg the conducting-wiresto prevent strain reaching the points of connection with thecontact-strips.

I claim- 1. In a spring-jack wedge or the like, the combination ofmetallic strips and an insulating-body separating them, withconducting-Wires electrically connected to the said strips and sewed tosaid body.

2. In a spring-jack wedge or the like, the combination of metallicstrips, an an insulating-body separating said strips and provided withtwo sets of perforations, with covered conducting-wires passing throu hone set of perforations in said body and e ectrically connected .to saidstri s, and bindingthreads. passing through t e second set ofperforations and through the covers of the Wires to secure the wires tothe body.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

. GUSTAVE A. ZUNDEL.

Witnesses:

EDITH J GRIswoLD, EDITH C. SARLEs.

